Re: [PATCH v2 for-4.20? 6/6] PCI: drop pci_segments_init()

[Roger Pau Monné <roger.pau@xxxxxxxxxx>]

On Mon, Feb 03, 2025 at 05:27:24PM +0100, Jan Beulich wrote:
> Have callers invoke pci_add_segment() directly instead. On x86 move the
> invocation back to acpi_mmcfg_init(), where it was prior to ????????????
> ("x86/PCI: init segments earlier").
> ---
> v2: New.
> 
> --- a/xen/arch/arm/pci/pci.c
> +++ b/xen/arch/arm/pci/pci.c
> @@ -88,7 +88,8 @@ static int __init pci_init(void)
>      if ( !pci_passthrough_enabled )
>          return 0;
>  
> -    pci_segments_init();
> +    if ( pci_add_segment(0) )
> +        panic("Could not initialize PCI segment 0\n");
>  
>      if ( acpi_disabled )
>          return dt_pci_init();
> --- a/xen/arch/x86/x86_64/mmconfig-shared.c
> +++ b/xen/arch/x86/x86_64/mmconfig-shared.c
> @@ -402,6 +402,9 @@ void __init acpi_mmcfg_init(void)
>  {
>      bool valid = true;
>  
> +    if ( pci_add_segment(0) )
> +        panic("Could not initialize PCI segment 0\n");

Do you still need the pci_add_segment() call here?

pci_add_device() will already add the segments as required, and
acpi_parse_mcfg() does also add the segments described in the MCFG.

Thanks, Roger.